US2743722A

US2743722A - Free diving apparatus

Info

Publication number: US2743722A
Application number: US468173A
Authority: US
Inventors: William B Mclean
Original assignee: Individual
Current assignee: Individual
Priority date: 1954-11-10
Filing date: 1954-11-10
Publication date: 1956-05-01
Anticipated expiration: 1973-05-01

Description

L mm W. B. M LEAN mm zzz FREE DIVING APPARATUS Filed Nov. 10, 1954 5 5/575 5 Ami; i

4 INVENTOR.

WlLLlAM B. MC LEAN KMWQM'M ATi'oRYs United States Patent FREE DIVING APPARATUS William B. McLean, China Lake, (Ialii.

Application November 10, 1954, Serial No. sear/s 7 Claims. (Ql. 128--142) (Granted Title 35, U. S. Code (1952), see. 266) The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

This invention relates to apparatus for providing breathable air at the correct pressure to an under water diver, and in particular to free diving apparatus in which the supply of breathable air is carried by the diver rather than supplied to him from the surface.

It is an object of this invention to provide improved free diving apparatus.

it is a further object or" this invention to provide free diving apparatus in which the volume of all the parts filled with breathable gas at breathing pressure is substantially less than the normal capacity of the lungs of the average human so that a separate conduit for exhaled gas is not required.

It is a still further object of this invention to provide free diving apparatus in which all water in the breathing system will collect by action of gravity at the exhalation valve, when the diver is in the normal swimming position, so that such water can be expelled when the diver exhales.

It is a still further object of this invention to provide free diving apparatus in which the pressure regulating valve is normally held in the closed position solely by the action of high pressure air in the supply line so that the pressure required to open the valve is reduced as the pressure in the storage tank reduces, thus permitting uniform breathing without the need of an auxiliary pressure reducing valve.

it is still another object of this invention to provide free diving apparatus in which the parts of the system which normally contain air at breathing pressure may be filled with water when not in use and which prevents the escape of air at such times.

It is a still further object of this invention to provide free diving apparatus which subjects the diver to minimum pressure differentials at those parts of his body most sensitive to pressure differentials.

Other objects and many of the attendants advantages of this invention will be readily appreciated as the same become better understood by reference to the following detailed description when considered in connection with the accompanying drawing wherein:

Fig. l is a section taken on line 1-1 of Fig. 2 with part of the invention shown in elevation, p

Fig. 2 is a section taken on line 22 of Fig. 1,

Fig. 3 is a side elevation of a diver wearing the free diving apparatus,

Fig. 4 is a section through the high pressure line, and

Fig. 5 is an enlarged sectional view of details of the pressure regulating valve.

In Fig. 1 and 2 the portions of the free diving apparatus which are tilled with breathable gas at breathable pressure, or the low pressure unit, areillustrated. Hollow cylindrical member, or case, has secured to it cover 2,743,722 Patented May 1,

12. In the example illustrated cover 12 is secured to case 10 by a plurality of screws 14. Case 10 and cover 12 can be made from any suitable material such as Bake lite, stainless steel, e tc. Flexible diaphragm 16, which in a preferred form is made of a suitable plastic, is mounted between case 10 and cover 12. The interior of case 10 and the inner wall of diaphragm 16 form low pressure chamber 18. Opening 24 is formed in cover 12 so that water at the ambient pressure of the sea may en gage the outer wall of diaphragm 16. Pressure regulating valve 22 is mounted in case 10. Valve 22 consists of valve casing 24 in which is formed valve seat 26, and valve body member 23. Valve casing 24 is rnade, in a preferred form, of brass, and member 28 is made of a suitable material such as nylon or teflon. Valve body member 28, see Fig. 5, is provided with a stem 30 which extends beyond valve casing 24 and into chamber 13 when member 28 is seated against valve seat 26 to shut valve 22. Casing 24 is secured in case it) by nut 32 which is threadedly secured on casing 24.. High pressure hose 34 is fixedly secured to casing 24 of pressure regulating valve 22. Lever arm 36, which is illustrated as being ring shaped as seen in Fig. 2 is pivotally mounted on valve casing 24 by screws 38. Lever arm 36 is "mounted so as to engage the end of stem Bit of valve body member 28 when lever arm 36 is moved away from cover 12 pivoting at screw 33 to open valve 22.

Exhalation, or exhaust, valve 40 comprises guard member a2 and flexible diaphragm 44- which is secured to case in by bolt 46 and nut 4-8. Diaphragm 44 is mounted so as to cover a plurality of openings 50 formed in casing 10. Guard 42 is spaced a short distance away from diaphragm 44 so that diaphragm 44 may move to uncover openings 50 to permit the contents of chamber 18 to escape, or to be vented, when the pressure within chamber 18 is greater than the ambient pressure of the surrounding water.

Central opening 52 is formed in case 10. Flexible air hose 54 has one end secured about the means forming opening 52. Mouthpiece 56 is mounted at the other end of flexible air hose 54 and is adapted to be held in the mouth of the diver.

Referring now to Fig. 3, tank 53 which contains a supply of breathable gas under high pressure, i. e., for example 2000 pounds per square inch, is mounted on the back of the diver by means of a conventional har ness which is not illustrated. Tank 58 has a valve 60 which is open when the diver desires to receive air from the tank. High pressure line 34 runs from the outlet of valve 60 to regulating valve 22. The pressure of the gas within line 34 is substantially that which exists Within tank 58 and no intermediate pressure reducing valve is used or necessary. High pressure line 3d is provided with a restricted opening 62, as seen in 4, which limits the maximum rate of how of gas into line 34. As a result if line 34 is broken or disconnected from pressure regulating valve 22 in any manner, the free end of line 34 will not whip about in the water and possibly injure the diver.

When the diver inhales, the pressure within chamber 18 decreases below that of the ambient pressure of the water. Diaphragm It? moves away from cover 1 2. and into chamber 18 as a result of the pressure differential. The movement of diaphragm 16 causes lever arm 36 to press stem 30 inward to move valve body 23 away from valve seat 26. The diameters of valve body 28 and stem 30 are such that air can flow around body 23 and stem 30 when body 28 is moved away from sealing engagement with valve seat 26. This opens valve 22 and perm'its air-frombigh pressure line 34 to enter into chamber 18. Valve casing 24 has grooves 64 formed on the rounded surface 66 about opening 68 so that the lever arm 36 cannot seal opening 68 and prevent air from entering chamber 18.

As the diver inhales, the breathable air enters the chamber 18 and is drawn through breathing hose 54 into his mouth through mouthpiece 56 and thence into his lungs. During inhalation the decreased pressure within chamber 18 causes diaphragm 44 to seal openings 50 of exhalation valve and thus prevent water from entering into chamber 18 through the openings 50. At the termination of inhalation, the pressure differential between the air in chamber 18 and that of the pressure of the water acting on diaphragm 16 decreases. The action of the high pressure air against valve body member 28 causes the valve body member to seat against valve seat 26 to close valve 22 and move lever arm as outwardly. At this time the diaphragm r6 ofiers no resistance to the movement of lever arm 36.

When the diver exhales, the exhaled air passes from his lungs through mouthpiece 56, hose 54 into chamber 18. During exhalation the pressure within chamber 1? is increased so that it is greater than the ambient pressure of the sea. Diaphragm 44 is forced by the pressure away from openings and the exhaled air is vented into the sea.

As seen in Fig. 3, case 10 is mounted high on the chest of the diver. There is a twofold reason for this location of case 10. The portion of the diver which is most sensitive to pressure differential is the lips and mouth rather than the lungs since the walls of the lungs are reinforced by the ribs while the lips and cheeks are unsupported by bone structure. By mounting case 10 as close to the mouth of the diver as is possible, the difference between the pressure of the sea and the pressure within chamber 13 acting on diaphragm 16 is normally only a few inches of water at the most and thus the pressure exerted against the lips and mouth of the diver are so small as to not be uncomfortable. Locating case 10 close to the divers mouth also reduces the length of flexible breathing hose 54 required, and as a result, the volume of chamber 18 and hose 54 is minimized. The volume of chamber 18 and hose 54, in a preferred example, is 4 fluid ounces, which is less than 0 the 64 fluid ounces which is the lung capacity of the average human. As a result only a small portion of the exhaled air remains in chamber 18 and hose 54 and is rebreathed when the diver inhales.

Exhalation valve 40 is mounted when the diver is in the normal swimming position, so that it is at the lowest point of chamber 18. Thus any water that may be admitted into chamber 18 will collect near valve 40 and will be vented into the sea when the diver exhales. Pressure regulating valve 22 is mounted beside exhalation valve 40 as seen in Fig. 2. Even if chamber 18 is full of water when the diver inhales, the high pressure air from valve 22 blows the water away from opening 52 so that the diver will be able to breathe air rather than inhale water.

The diver may desire to leave the free diving apparatus at the bottom of the sea while he swims about on the surface, or leave the mouthpiece out of his month while swimming on the surface. When the diver removes mouthpiece 56 from his mouth, hose 54 and chamber 18 will fill with water. However, no air will enter chamber 18 through regulating valve 22 since the pressure within the chamber will equal that of the sea acting against diaphragm 16 and thus there will be no pressure differential to open valve 22, which is normally biased closed by the action of the high pressure air in line 34 It is, therefore, not necessary to shut valve 60 of tank 58 under these conditions. When the diver wishes to again use the free diving apparatus, he exhales into the mouthpiece 56. A small portion of the air within his lungs is sufiicient to eliminate water within hose 54 and chamher 18 since their total volume is less than 0 the normal volume of the divers lungs.

Obviously many modifications and variations of the present invention are possible in the light of the above teachings. It is, therefore, to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.

What is claimed is:

1. Free diving apparatus for an under water diver comprising a chamber, valve means for admitting high pressure gas into said chamber when the pressure within the chamber is less than the ambient pressure of the water, conduit means for conducting high pressure breathable gas from a source of said valve means, and means associated with the chamber for permitting the contents of the chamber to escape when the pressure within the chamber is greater than the ambient pressure of the water, and means for communicating the interior of the chamber with the lungs of the diver, the combined volume of the chamber and communicating means being substantially less than the normal lung capacity of the average human.

2. Free diving apparatus for an under water diver comprising a chamber, valve means for admitting high pressure gas into said chamber when the pressure within the chamber is less than the ambient pressure of the water, conduit means for conducting high pressure breathable gas from a source to said valve means, means associated with the chamber for permitting the contents of the chamber to escape when the pressure within the chamber is greater than the ambient pressure of the water, and

means for communicating the interior of the chamber with the lungs of the diver, the volume of the chamber and communicating means being substantially equal to 4 the normal lung capacity of the average human.

3. Free diving apparatus for an under water diver comprising a source of pressurized breathable gas, a chamber, a conduit, a pressure regulating valve, said conduit conducting breathable gas from said source to said regulating valve, said pressure regulating valve admitting gas from said source into said chamber when the pressure Within the chamber is less than the ambient pressure of the water, exhaust valve means for venting the chamber when the pressure within the chamber is greater than the ambient pressure of the water, and means for communicating the interior of the chamber with the lungs of the diver, the volume of the chamber and communicating means being substantially A the normal lung capacity of the average human.

4. Free diving apparatus for an under water diver comprising means forming a chamber, a pressure regulating valve mounted in the chamber, a high pressure line adapted to conduct high pressure breathable gas from a source to the pressure regulating valve, said pressure regulating valve opening when the pressure within the chamber is less than the ambient pressure of the water to admit breathable gas into said chamber, an exhalation valve mounted in the means forming the chamber for allowing the contents of the chamber to escape when the pressure within the chamber exceeds the ambient pressure of the water, and a flexible hose having a mouthpiece in communication with said chamber, the mouthpiece of said hose adapted to be held in the mouth of the diver, the volume of the hose and chamber being substantially the volume of the divers lung capacity.

5. Free under water diving apparatus comprising a source of pressurized breathable gas, means forming a chamber, a portion of said means forming a chamber comprising a flexible wall portion exposed on its outer side to the ambient pressure of the Water surrounding the apparatus, a pressure regulating valve mounted in said means forming a chamber, a high pressure conduit extending from the source of breathable gas to the pressure regulating valve, said pressure regulating valve admitting breathable gas into the chamber when the pressure within the chamber is less than the ambient pressure of the water an exhalation valve for venting the chamber when the pressure within the chamber is above the ambient pres sure, and a flexible hose having a mouthpiece in communication with the chamber, the volume of the hose and chamber being substantially 5 the normal lung capacity of the diver.

6. Free diving apparatus for an under water diver comprising a hollow case, a cover for said case, a flexible diaphragm secured between said case and said cover, the interior of the case and one wall of said diaphragm forming a chamber, an opening in said cover so that the other wall of said diaphragm is exposed to the ambient pressure of the water, a high pressure line, a pressure regulating valve mounted in said case, said high pressure line having one end attached to and adapted to conduct high pressure breathable gas to the pressure regulating valve from a suitable source, a lever pivotally mounted on said valve mounted within said chamber, said lever arm adapted to be moved by said diaphragm when the pressure within the chamber is less than the ambient pressure of the water to open said valve and admit breathable gas into said chamber, an exhalation valve mounted in said case at the lowest position of said chamber when the diver using the apparatus is in the normal swimming position, said exhalation valve comprising a plurality of openings through the case communicating said chamber with the Water surrounding said case, a flexible diaphragm mounted on the exterior of said case for closing said exhalation valve openings when the pressure within the chamber is less than the ambient pressure of the water, and a protective cover for said exhalation valve diaphragm mount-ed on said case over said diaphragm and slightly spaced therefrom so that said diaphragm is between said case and said protective cover, said pressure regulating valve being mounted closely adjacent said exhalation valve, a flexible breathing hose having one end thereof mounted on said case so that said breathing hose is in communication with said chamber, and a mouthpiece at the other end of said flexible breathing hose.

7. Free diving apparatus for an under water diver comprising a hollow case, a cover for said case, a flexible diaphragm secured between said case and said cover, the interior of the case and one wall of said diaphragm forming a chamber, at least one opening in said cover so that the other wall of said diaphragm is exposed to the ambient pressure of the water, a high pressure line having a re stricted passage for limiting the rate of gas flow therethrough, a pressure regulating valve mounted in said case, said high pressure line having one end attached to and adapted to conduct high pressure breathable gas to the pressure regulating valve from a suitable source, a lever arm pivotally mounted on said valve mounted within said chamber, said lever arm adapted to be moved by said diaphragm when the pressure within the chamber is less than the ambient pressure of the water to open said valve and admit breathable gas into said chamber, an exhalation valve mounted in said case at the lowest position of said chamber when the diver using the apparatus is in the normal swimming position, said exhalation valve comprising a plurality of openings through the case com municating said chamber with the Water surrounding said case, a flexible diaphragm mounted on the exterior of said case for closing said openings when the pressure within the chamber is less than the ambient pressure of the water, and a protective cover for said exhalation valve diaphragm mounted on said case over said diaphragm and slightly spaced therefrom so that said diaphragm is between said case and said protective cover, a. flexible breathing hose having one end thereof mounted on said case so that said breathing hose is in communication with said chamber, and a mouthpiece at the other end of said flexible breathing hose.

References Cited in the file of this patent UNITED STATES PATENTS 2,682,871 Arpin July 6, 1954 2,695,609 Nourse et al Nov. 30, 1954 FOREIGN PATENTS 129,382 Australia Oct. 11, 1948 284,946 Switzerland Ian. 5, 1953